<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 头部的警告区域 -->
      <el-alert title="注意: 只允许为第三级分类设置相关参数!" type="warning" :closable="false" show-icon>
      </el-alert>
      <!-- 选择分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联 选择框 -->
          <el-cascader :options="categories" :props="{ expandTrigger: 'hover',...cascaderProps }" v-model="selectedKeys" @change="parentCateChanged" clearable></el-cascader>
        </el-col>
      </el-row>
      <!-- tab页答区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible =true">添加参数</el-button>
          <!-- 参数列表区域 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开列 -->
            <el-table-column label="序号" type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue" ref="saveTagInput" size="small" @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column label="序号" type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作" width="300px">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeUserById(scope.row)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加属性的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible =true">添加属性</el-button>
          <!-- 参数列表区域 -->
          <el-table :data="onlyTabData" border stripe>
            <!-- 展开列 -->
            <el-table-column label="序号" type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue" ref="saveTagInput" size="small" @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column label="序号" type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作" width="300px">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeUserById(scope.row)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加参数数据的表单 -->
    <el-dialog :title="'添加'+titleText" :visible.sync="addDialogVisible" width="50%" @close="addDialogClosed">
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 修改参数数据的表单 -->
    <el-dialog :title="'添加'+titleText" width="50%" :visible.sync="editDialogVisible" @close="editDialogClosed">
      <!-- 内容主体区域 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="auto">
        <el-form-item label="分类名称" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <!-- 底部区域 -->
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editUserInfo">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      //所有的商品分类数据列表
      categories: [],
      //指定级联选择器的配置对象
      cascaderProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      //选中分类的ID数组
      selectedKeys: [],
      //被激活的页签的名称
      activeName: 'many',
      //动态参数的数据
      manyTableData: [],
      //静态属性的数据
      onlyTabData: [],
      //控制添加对话框的显示与隐藏
      addDialogVisible: false,
      //添加数据的表单对象
      addForm: {
        attr_name: ''
      },
      //添加表单的验证规则对象
      addFormRules: {
        attr_name: [{ required: true, message: '请输入参数名称', trigger: 'blur' }]
      },
      editFormRules: {
        attr_name: [{ required: true, message: '请输入参数名称', trigger: 'blur' }]
      },
      //查询分到的分类数据
      editForm: {},
      //控制修改对话框的显示与隐藏
      editDialogVisible: false
    }
  },
  methods: {
    // 获取商品分类数据列表
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类失败')
      }
      this.categories = res.data
    },
    //选择项发生变化触发这个函数
    parentCateChanged() {
      this.getParamsData()
    },
    // tab页签点击事件的处理函数
    handleTabClick() {
      this.getParamsData()
    },
    //获取参数的列表数据
    async getParamsData() {
      //证明选中的不是三级分类
      if (this.selectedKeys.length !== 3) {
        this.selectedKeys = []
        this.manyTableData = []
        this.onlyTabData = []
        return
      }
      //证明选中的是三级分类
      //根据所选分类的ID，和当前所处的面板，获取对应的参数
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, { params: { sel: this.activeName } })
      if (res.meta.status !== 200) {
        return this.$message.error('获取参数列表失败')
      }
      res.data.forEach(item => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        //控制文本框的显示与隐藏
        item.inputVisible = false
        //文本框输入的值
        item.inputValue = ''
      })
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTabData = res.data
      }
    },
    //监听修改分类信息对话框的关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    //点击按钮添加参数
    addParams() {
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) return
        //可以发起添加参数请求
        const { data: res } = await this.$http.post(`categories/${this.cateId}/attributes`, {
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName
        })
        if (res.meta.status !== 201) {
          return this.$message.error('添加参数数据失败')
        }
        //关闭对话框
        this.addDialogVisible = false
        this.getParamsData()
        this.$message.success('添加参数数据成功')
      })
    },
    //重置编辑信息及规则
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },
    //点击编辑查询参数
    async showEditDialog(data) {
      const { data: res } = await this.$http.get(`categories/${data.cat_id}/attributes/${data.attr_id}`, {
        attr_sel: this.activeName
      })
      if (res.meta.status !== 200) {
        return this.$message.error('查询参数信息失败')
      }
      this.editDialogVisible = true
      this.editForm = res.data
    },
    //修改参数信息提交
    editUserInfo() {
      this.$refs.editFormRef.validate(async valid => {
        if (!valid) return
        //发修改用户信息的数据请求
        const { data: res } = await this.$http.put(`categories/${this.editForm.cat_id}/attributes/${this.editForm.attr_id}`, {
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName
        })
        if (res.meta.status !== 200) {
          return this.$message.error('更新参数信息失败')
        }

        //关闭对话框
        this.editDialogVisible = false
        //获取参数列表数据
        this.getParamsData()
        //提示修改成功
        this.$message.success('更新参数信息成功')
      })
    },
    //根据ID删除相对应的参数信息
    async removeUserById(data) {
      //弹框询问是否删除数据
      const confirmResult = await this.$confirm(`此操作将永久删除该${this.titleText}, 是否继续?`, '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)
      //如果用户确认删除，则返回值为字符串 confirm
      //如果用户取消了删除，则返回为字符串 cancel
      if (confirmResult !== 'confirm') {
        return this.$message.info('已取消删除')
      }
      const { data: res } = await this.$http.delete(`categories/${data.cat_id}/attributes/${data.attr_id}`)
      if (res.meta.status !== 200) {
        return this.$message.error('删除参数信息失败')
      }
      //提示删除成功
      this.$message.success('删除参数信息成功')
      //获取参数列表数据
      this.getParamsData()
    },
    //文本框失去焦点，或按下确认键都会触发事件
    async handleInputConfirm(row) {
      if (row.inputValue.trim().length === 0) {
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      //如果没有return，证明输入的内容，需要做后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      //需要发起请求，保存这次操作
      this.saveAttrVals(row)
    },
    //编辑提交参数
    async saveAttrVals(row) {
      //需要发起请求，保存这次操作保存到数据库
      const { data: res } = await this.$http.put(`categories/${row.cat_id}/attributes/${row.attr_id}`, {
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        attr_vals: row.attr_vals.join(' ')
      })
      if (res.meta.status !== 200) {
        return this.$message.error('更新参数信息失败')
      }
      this.$message.success('更新参数信息成功')
    },
    //点击按钮，展示文本输入框
    showInput(row) {
      row.inputVisible = true
      //让文本框自动获取焦点
      //$nextTick方的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    //删除对应的参数可选项
    handleClose(i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row)
    }
  },
  created() {
    this.getCateList()
  },
  computed: {
    //如果按钮需要被禁用，则返回true,否则返回false
    isBtnDisabled() {
      if (this.selectedKeys.length !== 3) {
        return true
      }
      return false
    },
    //当前选中的三级分类的ID
    cateId() {
      if (this.selectedKeys.length === 3) {
        return this.selectedKeys[2]
      }
      return null
    },
    //动态计算标题的文本
    titleText() {
      if (this.activeName === 'many') {
        return '动态参数'
      }
      return '静态属性'
    }
  }
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}
.el-tag {
  margin: 10px;
}
.input-new-tag {
  width: 120px;
}
</style>